1. Field of the Invention
The present invention relates to a method of attaching a die using a self-assembling monolayer and a package substrate including a die attached thereto using a self-assembling monolayer.
2. Description of the Related Art
Currently, electronics industries are making efforts to provide reliable electronic products which are miniaturized and reduced in weight and have multifunctionality and high performance. One of technologies which enable these goals to be accomplished is a packaging technology. In particular, a SIP (System In Packaging) technology based on a printed circuit board, which is one of packaging technologies for improving a surface-mount efficiency, is being intensively studied.
The SIP technology may be classified into a surface-mount technology (SMT) in which a die is mounted on a surface of a printed circuit board and an embedded active die (EAD) technology in which a die is mounted in a printed circuit board, any of which is performed using a die attach apparatus.
FIG. 1 is a schematic view showing a conventional die attach apparatus. The conventional die attach apparatus and a method of attaching a die using the die attach apparatus are now described with reference to FIG. 1.
As shown in FIG. 1, the conventional die attach apparatus 10 comprises a die loading unit 20, a slide glass 30, visual cameras 30a and 30b, and a die bonding unit 40.
The die loading unit 20, which is intended to pick up individual dies D which are diced from a wafer W and to transfer the dies to the slide glass 30, comprises a pickup head 22 for loading. In this regard, the die D is provide thereon with pads P and is provided at a bottom surface with a die attach film (DAF) attached thereto.
The slide glass 30 functions to allow positions of corners of the die D and positions of the pads P to be recognized by the visual cameras 30a and 30b, and is made of transparent material. In other words, disposition of the die D on the transparent slide glass 30 enables the visual cameras 30a and 30b to detect positions of corners of the die D and positions of the pads P.
The visual cameras 30a and 30b is intended to recognize positions of corners of the die D and positions of the pads P, and are composed of an upper visual camera 30a positioned above the slide glass 30 and a lower visual camera 30a positioned below the slide glass 30.
The die bonding unit 40 is intended to pick up the die D and to attach the die D to a substrate 50, and includes a pickup head 42 for bonding. The die bonding unit 40 attaches the die D to the substrate 50, based on the positions of corners of the die D and positions of the pads P detected by the visual cameras 30a and 30b. 
However, in order to attach the die D to the substrate 50 using such a conventional die attach apparatus 10, the slide glass 30 and the image recognition process using the slide glass 30 are absolutely required. In this regard, because dicing errors are incurred in the course of dicing individual dies from a wafer W, all of positions of corners of the die D and positions of the pads P must be detected so as to reduce errors in alignment, as shown in FIG. 2. To this end, use of the slide glass 30 is essential so as to detect both upper and lower surfaces of the die D using the visual cameras 30a and 30b. 
The image recognition process using the slide glass 30 has problems in that the process time is extended because the process is executed in a manner such that the die D is loaded and placed on the slide glass 30, positions of corners and pads of the die D are recognized using the visual cameras 30a and 30b, and the die D is picked up by the die bonding unit 40 and then mounted on the substrate 50.
Furthermore, because the die D is firmly adhered to the slide glass 30 owing to adhesive force of a die attach film (DAF) attached to a lower surface of the die D, it is hard to separate the die D from the slide glass 30 in the course of pickup of the die D.
In addition, when the lower visual camera 30b recognizes positions of corners of the die D through the slide glass 30, intensity of reflected light is reduced due to low reflective force of the die attach film DAF, thus severely deteriorating a recognition rate of the positions of corners.